A car has struck a group of cyclists who were on a school camping trip, killing three children and an adult in the rural southern Netherlands.
Police said in a statement on Thursday they detained a 19-year-old man and were investigating his involvement.
Two children and an adult died at the scene. Four children were seriously injured and were taken to hospitals in the Netherlands and nearby Belgium for treatment. One of them died on Thursday evening at a hospital in Rotterdam, the Zeeland Security Region organisation said in a statement.
Those who were killed and injured were part of a group of 14 schoolchildren and two chaperones from a primary school in the nearby town of Axel.
Police are investigating the cause of the incident on a provincial road that runs between farmers' fields near the small town of Vogelwaarde, about 200km south of Amsterdam.
A photo displayed on Dutch media showed a car, with its windshield smashed and bonnet damaged, in a field next to the road.
Such incidents involving multiple cyclists are rare in the Netherlands, where bicycle riding is woven into everyday life and almost all roads have dedicated cycle lanes.
No further details were immediately available.
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